Použití OS Linux pro měřicí aplikace

PŘÍLOHA B. ZDROJOVÝ KÓD - SEKUNDOVÝ GENERÁTOR S HPET ČASOVAČEM}i n t main ( ) {s t r u c t t i m e s p e c t t s , t t s _ a f t e r , t t s _ d e l t a ;const s t r u c t t i m e s p e c i n t e r v a l _ u p = {0 ,100000000};s t r u c t t i m e s p e c interval_down = {0 ,900000000 −CORRECT_SYST} ;s t r u c t sched_param s c h e d u l i n g _ p a r a m e t e r s ;i n t count = 0 ;comedi_t ∗ i t ;i n t subdev = 2 ;i n t chan = 0 ;/∗ Lock pages i n r e a l memmory ∗/m l o c k a l l (MCL_CURRENT|MCL_FUTURE) ;/∗ Setup p r i o r i t y o f p r o c e s s ∗/s c h e d u l i n g _ p a r a m e t e r s . s c h e d _ p r i o r i t y = sched_get_priority_max (SCHED_FIFO) − 4 ;/∗ Setup s c h e d u l i n g s t r a t e g y ∗/i f (0 != pthread_setschedparam ( p t h r e a d _ s e l f ( ) , SCHED_FIFO , &s c h e d u l i n g _ p a r a m e t e r s ) ){p e r r o r ( " pthread_setschedparam ␣ e r r o r " ) ;}/∗ Open Comedi d e v i c e ∗/i t = comedi_open ( "/ dev / comedi0 " ) ;/∗ C o n f i g u r e l i n e s to DO ∗/comedi_dio_config ( i t , subdev , chan ,COMEDI_OUTPUT) ;}/∗ Get time to measure r u n n i n g time ∗/c l ock_gettime (CLOCK_REALTIME,& t t s ) ;f o r ( count = 0 ; count < CNT; count++) {comedi_dio_write ( i t , subdev , chan , 1 ) ;n a n o s l e e p (& i n t e r v a l _ u p , NULL) ;comedi_dio_write ( i t , subdev , chan , 0 ) ;n a n o s l e e p (& interval_down , NULL) ;}/∗ Get time to measure r u n n i n g time ∗/c l ock_gettime (CLOCK_REALTIME,& t t s _ a f t e r ) ;d e l t a _ t (& t t s _ d e l t a , &t t s , &t t s _ a f t e r ) ;p r i n t f ( " Total ␣ w a i t : ␣%l u ␣ s e c ␣%l u ␣ nsec \n" , t t s _ d e l t a . tv_sec , t t s _ d e l t a .tv_nsec ) ;comedi_close ( i t ) ;return 0 ;30